This invention relates to water supply systems.
It is known in the water supply system art to have a pressurized water tank communicating with a well pipe through a submersible pump. In these systems, the pump is controlled by a sensing system to maintain pressure in the water system. The water may be supplied to households or to other plumbing or water systems.
In one prior art water supply system of this type, the pressure tank and associated equipment are mounted in a pit. The well casing extends upwardly into the bottom of the pit and connected there to pipes leading to the pressure tank where access is available to the connection. This arrangement has a serious disadvantage in that the pit accumulates waste water and the like and may permit contaminants to drain into the well.
In another class of prior art water supply systems known as pitless systems, this disadvantage is avoided by using a pitless unit or pitless adapter which is a unit that connects to the well casing, usually below the frost line, and conducts water to a pressure tank, protects the water from freezing and prevents the entry of contaminants. In a common type of pitless system, the pitless unit rests on the well casing below ground and extends upwardly to the surface. This type of pitless unit is approximately the same size as the well casing or one nominal size larger in the case of a spool type outlet to the plumbing system of the user. Usually, the pumps are driven by a constant speed motor that operates in duty cycles, has relatively constant flow rates depending on the efficient running speed of the pump motor but has different frequencies of the cycles of pumping and not pumping or durations of the cycles of pumping and not pumping that depend on the demand for water. The pressure tank is mounted separately from the well such as in a home or separate opening in the ground below the frost line or building near the well. The pressure tanks are sufficiently large to provide water under adequate pressure under different demand conditions with the same flow rate from the pumps but different frequencies of cycles or different duty cycles.
It is known to use variable speed pumps in water supply systems. Moreover, it is known to improve existing systems with a pit by sealing the pit with an enlarged housing of sufficient size to fill the pit, but these prior art retrofit systems also have large pressure tanks and the pressure tanks are mounted separately from the well.
This type of prior art water supply module has several disadvantages such as for example: (1) the size of pressure tank needed to satisfy demand for some plumbing systems is relatively large; (2) a separate building or space in the building receiving water from the well or other underground opening is needed for the pressure tank; and (3) they are relatively expensive to install, under some circumstances, because the pressure tank is located or housed at a location spaced from the well.
Accordingly, it is an object of the invention to provide a novel water supply system.
It is a still further object of the invention to provide a novel water-supply system that is economical to install.
It is a still further object of the invention to provide a water supply system that is economical and convenient to maintain and use.
It is a still further object of the invention to provide an economical water supply system.
In accordance with the above and further objects of the invention, a water supply system includes a water supply module that cooperates with a variable flow-rate pumping system to provide water from a well to a plumbing system such as a plumbing system of a building or a stand-alone water source in a park or the like. The variable flow rate pumping system can be any type such as a pump driven by a variable speed motor, the speed of which varies with an input signal related to water pressure or a constant speed motor driving a pump with the flow rate to the pressure tank being controlled by a cycle stop valve and a pressure switch that responds to pressure in the system. The water supply module includes a pressure tank and a pressure sensor or cycle stop valve connected to maintain pressure in the system by supplying water to the pressure tank at a higher rate when demand is greater. The casing of the water supply module is larger than the size of the well casing by more than a nominal size and is sufficiently large to receive the pressure tank within it. The drop tube extends through an opening in a bottom-closing member into the well casing. The closing member is required because of the larger size of the housing but may have the disadvantage of receiving condensation. Preferably some measures are taken to avoid rust and corrosion from moisture in the water supply module.
The pressure tank is dimensioned so that it fits within the water supply module housing and preferably sufficiently small to provide clearance in the water supply housing for other components to be inserted from above. For example, the clearance may be sufficient to permit lowering of the drop tube and pumping system from above. In the preferred embodiment, a pressure tank with a volume in the range of one to 15 gallons and still more preferably in the range of 2.2 to 4.5 gallons is used.
To prevent corrosion or contamination of the water from drainage in the water supply module, the water supply module: (1) is closed to prevent water from outside the module from entering the module; and (2) the water supply module includes a suitable means for removing water caused by condensation or leakage such as for example a desiccant or a sloped bottom member which may permit collection of moisture and drainage into the well and may be made of special materials to prevent rust and growths from occurring in the inside of the housing for the water supply module. The top of the module is closed by a cover to prevent contaminants from entering the housing and being carried into the well with moisture.
An opening in the bottom member of the water supply module housing, and in some embodiments, a tube that extends from the water supply housing to rest on and preferably seal against the well casing have a sufficient diameter for the drop tube to pass through them and have enough clearance for the pump and the pump motor to pass through. The opening may offset from the side of the water supply module housing to provide sufficient clearance between the pump and the pump motor when being lowered and the pressure tank, water supply module housing wall and well casing. Preferably, the clearance is sufficient to satisfy the requirements of all state agencies and organizations in the states such as the PAS 1997 standard. Slip joints are provided to permit the pressure tank to be inserted and removed from the water supply module from above without disturbing the pumping system or isolation valve leading to the plumbing system.
As can be understood from the above description, the water supply system of this invention has several advantages, such as: (1) it can be easily installed from the top of the well; (2) it can be easily maintained because the parts are easily removable through the top of the well or the well casing; and (3) it is economical in construction, installation and maintenance.